Ultrasound assisted cold-induced aggregation: an improved method for trace determination of volatile phenol

Evaluation of total phenol pollution in water of San Martin Canal from Santiago del Estero, Argentina

Santiago del Estero is a province located in northwestern Argentina. The Dulce River is used for irrigation through a vast network of channels and ditches, including the San Martin Canal (SMC), which crosses the capital city of Santiago del Estero. This canal's water is used for drinking, as well as recreational use for the general population. However, this river has been seriously polluted for several decades. The present study focuses on the identification and the quantification of the water pollution levels of total phenols in the SMC according to the seasonal periods. Water samples from various areas of the canal in different months of the year, extending from December to September, were collected for analysis. Additionally, the concentration of total dissolved solids (TDS), chlorides, sulphates, nitrites and organic matter, as well as water hardness and alkalinity, were analysed in order to conduct a more complete study of the contamination of this area. The results showed a worrying total phenol concentration that exceeded the limit set by Argentine legislation for drinking water, as well as water for recreational use (5 μg/L). The total phenol (TP) concentration was directly determined by a molecular absorption spectroscopy method based on a new flow injection analysis system (FIA). Under the selected experimental conditions, the detection and quantification limits were 0.0490 and 0.1633 μg/mL, respectively. The developed method provides a number of improvements related to the speed of analysis, the restricted consumption of the reagents and sample volumes and the unnecessary sample treatment that contribute to environmentally friendly analytical chemistry. The results showed that TP make a significant contribution in the SMC pollution, especially during the months of April (400 ± 110 μg/L) and September (240 ± 20 μg/L). A high sulphate concentration that was higher than the limit allowed by the legislation was also found.

Research on the Treatment of the Yellow River Micro-Polluted Water in Shanxi by Ozone-Activated Carbon Process

In this study, the micro-polluted water of a reservoir filled with Yellow River water in Shanxi was used as the raw water. The removals of chemical oxygen demand (CODMn), ammonia nitrogen, petroleum substances, and volatile phenol were investigated by ozone-activated carbon process. Results showed that ozone-activated carbon process had a good removal of the pollutants mentioned above. The optimum dosage of ozone for each pollutant was 2.0 mg/L, 2.5 mg/L, 3.0 mg/L, 3.0mg/L, with the corresponding removal efficiency of 59.36 %, 88.01%, 79.31%, and 88.16%, respectively. The treated water quality could meet the standards for Drinking Water Quality (GB5749-2006) in China.